Your age probably determines when you think tablet computers were invented: 'Millennials' (a.k.a. Generation Y) are unlikely to look further back than Apple's first-generation iPad in 2010; Generation X types may recall Microsoft's 2002 Tablet PC launch and subsequent releases; and Baby Boomers (myself included) with fond memories of Star Trek, 2001: A Space Odyssey and A Hitchhiker's Guide to the Galaxy, will probably have (increasingly) vague recollections of the 1990s devices spawned by such science fiction — Apple's Newton-based MessagePads, early Fujitsu tablets, the first IBM ThinkPad, for example.
An evolving heritage
For a supposedly 'new' style of computing, tablets have a lengthy and convoluted heritage (remember Ultra Mobile PCs? They petered out in pre-iPad days and came back as today's small form-factor tablets). To get an impression of that still-evolving heritage, explore our Dipity timeline (above). We've included a lot of tablets (and tablet/notebook convertibles and hybrids), but do not claim to have covered every significant product. In particular, we haven't explored PDAs (which merged with mobile phones to become today's smartphones and phablets), beyond the Apple MessagePad. If you recall a particularly influential device that we've missed, do let us know — we'll keep updating and amending the timeline.